Although the keyboard remains a primary input device of a computer, the prevalence of graphical user interfaces (GUIs) may require use of a mouse or other pointing device such as a trackball, joystick, touch device or the like. Due to its compact size, the touch device has become popular and widely used in various areas of our daily lives, such as mobile phones, media players, navigation systems, digital cameras, digital cameras, digital photo frame, personal digital assistance (PDA), gaming devices, monitors, electrical control, medical equipment and so on.
A touch device features a sensing surface that can translate the motion and position of a user's fingers to a relative position on screen. Touchpads operate in one of several ways. The most common technology includes sensing the capacitive virtual ground effect of a finger, or the capacitance between sensors. For example, by independently measuring the self-capacitance of each X and Y axis electrode on a sensor, the determination of the (X, Y) location of a single touch is provided.